A new CDC study reports that the first updated Covid-19 vaccine—the bivalent vaccine approved in fall 2022—was about 50 percent effective in blocking infection over a two-month post-vaccination period in children and adolescents aged five to 17. But this limited and transitory benefit does not justify the agency’s official recommendation that everyone in this low-risk age group be vaccinated against Covid-19.
The CDC recommended the bivalent mRNA Covid-19 vaccine—containing the original virus and a later Omicron strain—for persons aged 12 or older on September 1, 2022, and for children aged five to 11 on October 12, 2022. The bivalent vaccine was superseded last fall by a univalent vaccine against a subsequent Omicron variant. Yet limited data are available on the bivalent vaccine and subsequent univalent vaccine’s protection against infection for children and adolescents.
The new study prospectively followed and administered weekly tests to 2,959 participants between the ages of five and 17. It found that the bivalent vaccine was 54.0 percent effective against infection and 49.4 percent effective against symptomatic Covid-19 when comparing those who received it with those who were unvaccinated or received only the original Covid-19 vaccine.
